They’re all different sizes, actually. But all are designed to keep the level of calories, carbohydrates, protein and fat the same within each group. When the calories and carbohydrates are the same in your daily meal plan, it’s easier to keep your blood glucose stable, says the American Diabetes Association (ADA).

It’s best to keep a list of serving sizes on your pantry or refrigerator door. At a glance, you can make sure you’re getting in all your recommended nutrients.

Here’s a list of what “one serving” is for some common food items:

1 slice bread

1 medium size apple, banana, orange

1 cup milk or yogurt

1 oz cheese

1 egg

1 cup raw vegetables

1/2 cup cooked vegetables

1/2 cup vegetable juice

1/2 cup cooked cereal

1/2 cup rice or pasta

1/2 cup fruit chopped, cooked or canned in water

1/2–3/4 cup fruit juice

1/3 cup cooked beans

3 oz cooked beef, poultry or fish

Reprinted from 101 Tips for Simplifying Diabetes by the University of New Mexico Diabetes Care Team. Copyright by the American Diabetes Association. Used by permission. All rights reserved.